Semtech Corp., a supplier of analog and mixed-signal semiconductors, today announced the SC654, SC657 and SC658LED backlight charge pump drivers for 6, 5, and 4 LEDs, respectively. Optimized for single-cell Li-ion battery applications, each part in this new platform is packaged in ultra-thin (0.6mm max.) 14-pin 2x2mm MLPQ package to provide the industry’s smallest solution in reliable and easy-to-handle plastic packaging.
Each member of the SC65x family integrates a high-efficiency charge pump, multiple low-dropout current sink regulators, and the proprietary one-wire SemPulse interface. The mAhXLife charge pump monitors each LED’s forward voltage and automatically selects between 1x, 1.5x and 2x modes to optimize efficiency as the battery voltage changes over time. The low-dropout current sink regulators provide LED current matching of 0.5% typical to ensure accurate and even illumination. LED current may be adjusted from 0mA to 25mA in 29 settings via the one-wire SemPulse interface.
In many modern handheld systems, the usual I²C serial bus is becoming over-burdened with too many slave ICs. In such cases, the SemPulse interface is highly preferred because it provides a simple means of programming many features while consuming only one GPIO on the baseband or applications/graphics processor. The interface is simple, robust, and very tolerant of sloppy timing caused by interrupts elsewhere in the system.
